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The weedy-seedy plants of fall

Three of Michigan’s most annoying weeds that produce seeds are hedge parsley, sandbur and common burdock.

Every fall,
hikers, walkers and gardeners – anyone who spends much time outside – run into
a similar dilemma. They look down at their pant legs and they are covered with
seeds that do not brush off. Or, they bump their head into some weed that is
loaded with seeds and those weed seeds become hopelessly entangled in their
hair. And there’s not just one seed, but hundreds.

Not only are
there loads of seeds sticking tightly, they will not come loose. Sometimes,
it’s faithful Fido who is coated after a romp in the great outdoors. To add
injury to insult, one of these plant’s burs can cause painful injuries if it
becomes embedded in skin.

Some of these
plants are biennial, taking two years to complete their life cycle. The first
year they are a small plant with no flowers or seeds, and the next year they
grow much larger and produce flowers and seeds, and then their life is over.

Several weedy-seedy
plants that make the “Very Annoying List” for all seed pickers are hedge
parsley, sandbur and common burdock.

Hedge parsley or spreading hedge
parsley

For many
parts of Michigan, this appears to be a new weed or one that is seen more
frequently in the last several years. This biennial plant grows in both sun and
shade and can grow to over 5 feet tall. The leaves are a rich, shiny green and
look slightly like flat-leaf parsley.

Plants
produce small, white flowers like tiny Queen Ann’s Lace on the upper part of
the plant. The seeds are extremely annoying and produced in wild profusion by August and later. The seeds are very small and
have rows of mini-hooks on them that secure them to every passing form of life.
In hair, they become matted clumps. On clothes, they cling tenaciously. Luckily,
they do not stick to canvas or denim well.

Hedge
parsley. Photo credit: Valter Jacinto, Flickr.com

Sandbur

This weed is
an annual, yellow-green, spreading annual grass that is mostly erect, but can
occasionally form mats. It thrives in dry, sandy soils and this is how it got its
name. The seeds are contained in a bur that has extremely sharp spines. Each
seedhead has multiple burs. Because the spines on the burs are so long and
sharp, they can cause a great deal of pain if contact is made.

Sandbur. Photo credit: Matt Lavin, Flickr.com

Common burdock

This biennialproduces thistle-like burs on a plant
that can range in size between 3 and 5 feet tall. The bristly bracts are hooked
and form a round seed head below a small tuft of lavender florets. Burdock burs
were the inspiration for the invention of Velcro.

Removal of
seeds can be a monumental task. There are a number of techniques to try to
remove the seeds, but wearing gloves may help protect your fingers while doing
this. Tools that might work with various seeds are lint rollers, sticky tape or
duct tape, fine tooth comb and a disposable razor. If hair or pets with hair
are involved, massage in vegetable oil, comb gently and then wash. Pet
“de-shedding” tools or scissors are recommended on pets.

Related Resources

David Smitley, Michigan State University Department of Entomology, and Deborah G. McCullough, Michigan State University Departments of Entomology and Forestry | Guidelines for homeowners with hemlock trees infested with hemlock woolly adelgid.